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Altera_Forum
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11 years ago

How does dither value affect the sine wave output of Altera NCO IP Core

Good day! I tried plotting a sine wave in Microsoft Excel by using the following equation in page 3-1 of NCO IP Core User Guide v14.1: s(nT) = Asin[2π(fO+ fFM)nT+ ϕPM+ ϕDITH)] ...
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Altera_Forum
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11 years ago

Hi kaz, thanks for the reply.

"did add a constant for dither, that will change phase by a constant value."

-> Yes, when I tried adding a constant for dither, the phase was changed by a constant value.

But is this the expected effect of dithering?

Based on page 3-6 of NCO IP Core User Guide v14.1, phase dithering provides improvement in SFDR by reducing noise localization.

"you should add random noise"

-> To where should I add noise?